Dear all, For a project I need to calculate the conditional AIC of a mixed effects model. Luckily, I found a reference in the R help forum for a function to be used:
CAIC <- function(model) { sigma <- attr(VarCorr(model), 'sc') observed <- attr(model, 'y') predicted <- fitted(model) cond.loglik <- sum(dnorm(observed, predicted, sigma, log=TRUE)) rho <- hatTrace(model) p <- length(fixef(model)) N <- nrow(attr(model, 'X')) K.corr <- N*(N-p-1)*(rho+1)/((N-p)*(N-p-2)) + N*(p+1)/((N-p)*(N-p-2)) CAIC <- -2*cond.loglik + 2*K.corr return(CAIC) } Reference: http://r.789695.n4.nabble.com/Using-Conditional-AIC-with-lmer-td847899.html However, in this function the function hatTrace of the lme4 package was used to calcuate rho (line: rho <- hatTrace(model) ) Sadly, R tells me that this function could not be found. A search on the internet revealed that this function was dropped out of the new package release of lme4. Can anyone help me with this? Is there an alternative function that gives me the same result as the hatTrace function? I searched the internet for solutions, but I could not find anything that is helpful. Thanks in advance, Bye, Inga -- View this message in context: http://r.789695.n4.nabble.com/Function-hatTrace-in-package-lme4-tp4646071.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.